Introduction to TRIZ: Brainstorm Design Problems by Avoiding Trade-Offs

TRIZ is a brainstorming method specifically designed to tackle engineering problems. The insight of TRIZ is that any design involves trade-offs or technical contradictions between two or more opposing features. But innovative solutions will apply one of the 40 TRIZ principles to avoid these trade-offs, and deliver a higher level of performance.

The story behind TRIZ is that Russian inventor Genrich Altshuller hit on the idea through a deep study of patents and inventions. Patents are legal applications that you file when you have a novel invention, to give yourself sole rights to use that invention for a period of time. By studying patents, the story goes that the same sort of innovations kept cropping up again and again in many different fields. Even though different problems had different solutions, these solutions shared a few key principles. In this post, I will give you a quick introduction to applying the 40 principles to your problems.

Just as a note before we continue, there are several other elements to TRIZ that I have not learned about. A whole area of knowledge, including seminars and computer programs and other things dedicated to TRIZ. So there is more to this than just the 40 Principles that we will discuss in this post.

Also, in my opinion TRIZ is primarily useful at solving mechanical engineering problems when you are designing new products. You can make it work for chemical engineering. Other people have tried applying it to fields like chemistry or finance. But I think if you get too far from engineering you are stretching it: I don’t think TRIZ will solve many marital problems.

Anyway, let’s try it. I personally have had one great success in my career using a TRIZ technique. I came up with a solution that cost only 25% of the obvious solution and required only 10% of the footprint.

Steps to TRIZ:

1. Consider your design problem, and make a list of the competing factors and fundamental trade-offs you are facing. This list is also called the list of technical contradictions. “I want to make X better, but if I do it makes Y get worse.” For example, it may be that making an object longer makes it weigh more, getting a more powerful motor costs more, higher temperatures require more energy consumption, etc.
2. Take a look at the TRIZ matrix (online, MS Excel). Do your best to fit the list of trade-offs you made in step 1 to the entries in the matrix. If you spot any brand new trade-offs while you are looking at the matrix, include them. You should write a list of pairs of contradictions during this step. (Note: you are supposed to do step 1 first. Do not just jump straight to the matrix! If you skip step 1, you can get tunnel-vision and may miss important trade-offs).
3. When you use your list of contradictions to look into the matrix, at most intersections of two contradictions you will see some numbers. These numbers refer to the 40 Inventive Principles (interactive online, single document). Look up the number in a list of the 40 principles, and read about what the principle is. To help you, the TRIZ Journal has made special lists of the 40 principles with different examples for different disciplines. (ex: Chemical engineering, chemistry, finance, business, etc). If there are no numbers shown at the intersection, then TRIZ has no suggestion for you.
4. Try to apply the principles your matrix suggests to your problem. Sometimes it won’t make any sense, but sometimes it will help you see a solution.

References:

Triz40.com for interactive html principles and quick lookup commands

Triz Journal for articles about TRIZ and examples of applying TRIZ to many disciplines

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Was that confusing? Let’s try a fictional example that I just made up for the purposes of this post. See if you can follow along.

1. A brand new catalytic reaction was just discovered. I try to design a reactor to industrialize the process. My design will work, but the economics need to be improved. Thinking, I decide I want to increase the temperature, because that will speed up the rate of the reaction. This lets me get a faster production, improving the economics. (Or, build a smaller reactor and get the same rate of production). The downside is that my vessel and the surrounding piping will have to cost more, largely because I have to use a more expensive metal for the walls and the internals. I want to avoid this trade-off. After all, my whole point was to improve the economics!
2. I take my problem, open up the TRIZ matrix, and come up with a few matrix entries to try: first I want to look up “Improving productivity worsens temperature”, and “Improving temperature worsens ease of manufacture.” Looking through the matrix I see “Use of energy by stationary object.” Hey! That’s a good point. If I increase the temperature of the reaction I will also increase my fuel costs. So I am also going to check “Improving temperature worsens use of energy by stationary object”. I could keep reaching, using my creativity to come up with more and more entries, but for now let’s just see what we get with these three contradictions.
3. For each of these entries, I can see what principles are suggested and then check the principles out. To start, I look up “Improving Productivity worsens temperature” and the matrix suggests principles #35, #21, #28, and #10. Try it on Triz40.com and confirm that I am right!
4. I open up my list of 40 principles to see what these suggested principles are and try to use them:

• #35, Parameter changes, mentions changing the concentration or consistency. Hmm. Maybe I could use distillation to increase the concentration of my reactants before they reach the reactor. That would speed up the reaction. Or maybe I should use smaller catalyst pieces.  That will provide a larger catalyst surface area for the reaction to take place. Either way, I could increase the rate of reaction without using a higher temperature at all! (Read about Factors Affecting Chemical Kinetics if this is foreign to you).
• #21, skipping, does not seem to apply to me.
• Neither does #28, mechanical substitution.
• How about #10, preliminary action? It says to perform, before it is needed, the change in an object. If my reaction is a two-stage process, maybe I can do one of the stages in a cold reactor, and one of the stages in a hot reactor, allowing me to make a smaller hot reactor. Or maybe the lab team can find another catalysis path that will work in several stages at a lower temperature. Or perhaps, what if I bought more chemically complex starting materials as feedstock for my plant – could I skip the hot step?

You can see the ideas are flowing now. I can keep looking up more TRIZ matrix entries and principles for ideas, or just work on the ideas I already came up with

This method is quick, and structured, so give it a try.

A last piece of general, less specific advice: the best solutions are usually simple and elegant, and largely created using the things that are already in your “problem workspace”. Try to make the most of what is already in front of you!